This is, of course, the second tragedy this year to befall the passengers of a Malaysian Airlines jet. But will it have an effect on the ongoing fighting and violence in Eastern Ukraine — and, by extension, U.S. relations with Russia? That will depend largely on which side is determined to be responsible. While there's still no smoking gun, there are some clues as to who might have shot down the Malaysian craft.

The commander of Russian separatists in the Ukrainian city of Donetsk, where the Malaysian Airlines plane crashed, took credit on social media for downing a plane. He claimed that it was a Ukrainian AN-26 flight, but he may have been mistaken.

The plane was flying high enough that it would have required an especially high-powered surface-to-air missile system in order to have been shot down from the ground. Russian separatists boasted on Twitter of having such weapons in late June; the tweet in question, however, has since been deleted.

Why It Might Not Be The Work Of Russians

All of that said, it’s too soon to say with any certainty whether or not this was the work of the Russians for a couple of reasons.

The Ukrainian craft that was downed by the Russian military was shot down by another plane, not a surface-to-air missile like the Malaysian jet, so in some sense it’s an unrelated incident.

Behavior from the leader of Ukrainian separatists in the region suggests that they, too, may possess a BUK missile system.

President Putin himself was supposedly on a flight that crossed paths with the Malaysian jet, so there is a theory that he was the target of an assassination attempt. However, the only source reporting this seems to be Russia Today, a pro-Russian site with ties to the Russian government, so it should be taken with a grain of salt.

Is This Terrorism?

The President of Ukraine referred to the incident as a “terrorist act.” But it’s highly doubtful that either side in would intentionally targeted a passenger flight; this was most likely either a case of mistaken identity, or some other manner of accident. Intentionally killing civilians is terrible PR for a nascent government — just ask ISIS in Iraq — and both the Ukrainian government and the Russian separatists are striving very hard to be perceived by the global community as the legitimate governing body in the region. That’s what the entire mini-war is being fought over; shooting down a civilian craft from a country that’s wholly unrelated to the local conflict would yield absolutely no benefit to either side.

Consequences For The U.S.

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Presumably, Russia and Ukraine will be at each other’s throats even moreso than they are now if and when one of the sides is deemed responsible. Beyond that, though, this could worsen U.S.-Russian relations if Russia is deemed to be involved. The U.S. is already allied with Ukraine in the current crisis, and Vice President Joe Biden has already offered assistance to Ukraine in its investigation. Furthermore, the Obama administration imposed a new round of sanctions on Russia just one day before the crash, and President Obama told Putin after the crash that “additional steps are on the table” if Russia doesn’t make moves to deescalate the fighting in Eastern Ukraine.

Still, it’s too soon to say. Nobody knows with certitude that the plane was even shot down, let alone who might have shot it down and why, so at this point, anything could happen.